Influence of Waste Plastic Dosage on Bituminous Concrete Mix Design Properties

Abstract

Nowadays there is a lot of focus and concern regarding handling waste plastics in order to minimize pollution caused by it to the environment, human life and marine species.  Hence to mitigate these problem waste plastics are currently used in the construction of flexible pavements.  In the current practices, waste plastics are added to the preheated aggregate which may have a slight improvement in the volumetric property of bituminous mixtures. Hence in order to the betterment of the volumetric properties of the bituminous mixtures, a novel method was adopted in this research work.  In the current study viscosity grade VG20 bitumen, waste plastic of type Low-density polyethylene (LDPE) and bituminous concrete grade II (BC II) with aggregate mid-gradation were used. Marshall mix design was carried at 0%, 2%, 4%, 6% and 8% dosage of LDPE waste plastic are added by weight of bitumen and tested the sample for Marshall stability and flow as per ASTM D6927-15. It was observed that the optimum dosage of LDPE waste plastic is found to be 6% for bituminous concrete grade II mixture and at this dosage level meets all criteria of Marshall properties as per MoRTH 2013.  Results showed that the marshall stability was more and flow value was less for the bituminous mixture prepared using the novel method when compared to the control method. It was also observed that there was less or no influence in theortical maximum specific gravity, bulk density, voids in mineral aggregate (VMA), and voids filled with bitumen (VFB) for Novel method when it is compared to the control method. Hence addition of waste plastic in flexible pavement could mitigate the environmental pollution caused by it.